How to increase or boost water pressure

Is your water pressure low, with a slow flow rate?

Are you dreaming of a powerful shower? Is your bath taking an age to fill up? Then, you need to know how to increase water pressure with a booster pump setup.

The flow rate at which water is delivered depends on two factors:

Water pressure is governed by how high your water reservoir, tower or pump station is compared to your property. Other factors like pressure regulators upstream of your property will reduce the effective water pressure. In simple terms, the pressure is measured by the water head (height). In a gravity-fed system, 1 bar of pressure will be felt if your water tank is 10 metres above your tap. 2 bar is 20 metres. 3 bar is 30 metres, etc.

Pipe diameter: The supply pipe diameter between the reservoir and your property will affect your tap's flow rate and water quantity. The water main feeds other properties, so you may have a drop in your water flow when it is most needed in peak times. Older properties may have a 1/2″ pipe. Newer housing will have a 1″ water main, which will help. Cities with lots of development may not have the water system infrastructure upgrades to supply all new dwellings and demand.

There are many reasons for increasing your water pressure but ultimately improving your quality of life. This is simple to achieve with a small investment in the correct hardware.

Can I install a booster pump directly in the main water pipe? 

You might think a simple solution would be to install a pump in the main water pipe. Thus increasing the water pressure. For several reasons, this is not a viable solution. Pumps are great at pushing water but are not designed to pull it. Pumping directly from the water main will make the pump remove water from the main (which may already be limited). This will drag down the pump capability and wear it out faster without much improvement in flow rate. Due to the water company and local bylaw regulations, pumps capable of delivering above 12 litres/minute will not be installed in the water main.

The solution

It's not difficult to achieve a reasonable flow rate for the whole house, but you need two key components:

  • A water break tank with a float valve
  • A water booster pump with an automatic control system.

Booster pump with automatic pump controlOn Demand Booster Water Pump

Install a break tank to create higher-than-mains water pressure.

The break water tank is supplied from the cold water supply and fills up with a float valve. The storage tank should be sized to allow for peak demand. Otherwise, there won't be enough capacity to fill your needs when you want to use the water. With space in the break tank, the water main refills it. Then, it turns off the water valve when it's full, ready for the subsequent demand. Your water meter shouldn't change too much since the same amount of water will be used thanks to the tank.

Typical sizes of break tanks will depend on the property size and the number of occupants.

A typical one or 2-bedroom flat with one bathroom: 125 L - 150 L water tank

A 3 or 4-bedroom house: a 200L to 250L water tank will work well.

A bigger tank will be required if you have multiple bathrooms, like a guest house or bed and breakfast. Depending on the expected peak demand.

It's best to install the break tank at ground level, where the main water flow will be at its best. The kitchen, utility room, and the nearest incoming water supply are the best places to install one.

Combining a water booster pump with the break tank

The water booster pump should be installed next to the break tank to push water to the rest of the dwelling's water main pipes. A good quality pump that is quiet in operation is a must.

Pressure and/or flow sensors control the pump, combine it into a compact unit, and plumb into the outlet port. This unit will automatically control the pump, switching the pump on when the pressure drops and switching the pump off when there is no demand. There are two main types of pump controllers for booster water pressure.

Pressure switch: This works by switching on and off at preset pressures. The switch could be set to turn on at a low of 1.5 bar and off at 2.8 bar. The "off" pressure setting must be below the maximum pump pressure. To help smooth out pressure spikes and hammering, you use this type of pressure switch with an expansion vessel. When you close a tap quickly, or the washing machine closes a valve, it regulates the pressure.

An all-in-one break tank and water booster pump system is a convenient installation for boosting water pressure. These packages are ready to install, complete with an automatic fill valve, overflow and pump controller. This makes installation very simple and efficient.  The Power Tank Booster Systems are available from 125L for smaller domestic properties to much larger systems for large commercial buildings and multiple dwellings using variable speed pumps.

Powertank booster Systems

Water Pump Controllers and Flow Switches

Flow Controller:  This works similarly to the pressure switch but has the advantage of not being limited to the pressure switch setting and can, therefore, use the maximum pressure of the pump as a flow switch is used to achieve the "off" switching. This style of flow controller has the advantage of a 'run-dry' protection system. If the controller detects no flow, the pump will switch off, which protects the pump. Most flow controllers have an automatic restart feature. , So if the pump runs dry and switches off, it will restart after a set period, allowing the break tank to refill.

Boosting water in hotels, larger homes or non-domestic properties

Hotels, guest houses and larger properties may have the same low flow rate issues, usually compounded by higher demands at peak times. Typically, a hotel where multiple guests would like showers at 7:30 AM or 6 PM. The solution is similar, but the equipment is slightly different. The break tank will need to be larger, so outside the main building or in a basement may be the best place for the installation. The pump system will require a higher level of control using variable speed pump controllers and multiple pumps to keep up with the varying flow rates and demand cycles. First, a consultant will assess the requirements and measure the main water inflow rate. Their assessment aids the designing of a system to maintain the desired flow rate and pressure throughout the demand cycle using the correct size water tank and variable speed water pumps with intelligent pump controllers to meet the demand and ensure smooth water flow.

Showers and how they work

We tend to suffer most from low water pressure when our shower head produces a little sprinkle. Shower pumps can alleviate this issue and are cheaper than you might think. Combi boilers can be disappointing in a larger house, so getting that little extra boost might be what you need. Otherwise, a good quality electric shower might be the answer as they take the generally higher pressure cold water and heat it directly at the shower.

You need to know a few things to boost your water pressure.

If the property's hot water cylinder doesn't vent (unvented pressurised tank, the hot water tank, and the heating system run from mains water plumbing (i.e. no water tank in the loft)), boosting your water pressure will increase water flow to both the cold and hot water supply equally. Which is perfect!

The above system will not boost the water flow if you have a cold water header tank in the loft. For instance, the height of your existing header tank determines this. You can pump from your cold water tank in the attic, but you must ensure you know how the heating system works.  We do not recommend boosting cold water pressure if you have a vented hot water system.

We always recommend a qualified plumber or heating engineer for booster system installations. All installations must comply with water bylaws and regulations.

OFWAT is an excellent source of information, especially for water pressure issues.

If you require further assistance or want to talk to someone about water pressure and how to boost it, contact us or call 01722 442446.